Suture anchors and assemblies for attaching soft tissue to bone

ABSTRACT

Improved bone anchors are disclosed for anchoring one or more sutures attached to soft tissue to a bone. The bone anchor has an anchor body that extends between a distal end and a proximal end. A bore is formed axially in the anchor body and opens at the proximal end. One or more pins are fixed within the bore of the anchor body. One or more sutures can be looped on the pins for anchoring soft tissue to bone. The anchor body has a socket within the bore for receiving a driver tool. The distal end of the anchor body forms a non-threaded extension, which stabilizes the bone anchor, and helps prevent lateral movement during use. In one embodiment, the anchor body has coarse threads for engaging soft bone tissue and fine threads for engaging hard bone tissue.

RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.13/297,913, filed Nov. 16, 2011, entitled “BONE ANCHORS FOR USE INATTACHING SOFT TISSUE TO BONE,” which is a division of U.S. patentapplication Ser. No. 11/317,204, filed Dec. 22, 2005, now issued U.S.Pat. No. 8,114,127, which is a continuation-in-part of U.S. patentapplication Ser. No. 10/873,987, filed Jun. 22, 2004, now issued U.S.Pat. No. 7,322,978, the disclosures of which are incorporated herein intheir entirety.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates to soft tissue repair surgery, such asrotator cuff repair surgery. More specifically, the present inventionrelates to a bone anchor used to attach soft tissue to bone using asuture.

2. Related Technology

Soft tissue injuries, especially rotator cuff injuries, can occur fromrepeated stress or acute trauma. The rotator cuff is a group of musclesand tendons in the shoulder that attach to the humerus bone of the arm.The rotator cuff allows a person to rotate the arm and raise it abovethe head. A common injury to the rotator cuff occurs when repeatedstress or acute trauma causes the rotator cuff to partially or completetear away from the humerus bone. These and similar types of injuries mayrequire surgery to correctly reattach the soft tissue to the bone.

Various devices have been used to reattach soft tissue to bone. Knownmethods include staples, wedges, plugs, screws, and sutures alone.Threaded suture anchors, such as bone screws, have recently beendeveloped to provide a particularly firm location where a suture can beanchored to bone. In these systems, a suture is tied between the boneanchor and soft tissue. Providing a firm attachment point for the sutureis important because of the relatively strong forces that areexperienced in a flexing muscle.

Despite recent advances in bone anchors, existing bone anchors androtator cuff repairs can fail and have other disadvantages. Typically, arotator cuff repair fails either because the bone anchor dislodges orthe suture tears through the soft tissue. As force is applied to thesuture, the suture can cut through the soft tissue like a cheese wire,leaving the rotator cuff detached from the humerus bone. When one suturefails, it can place more stress on the surrounding sutures, thusincreasing the likelihood that other sutures will fail in like manner.

Using a greater number of sutures per unit area of soft tissue canminimize suture attachment failure. However, the number of sutures islimited by the space available for inserting bone anchors.Alternatively, additional sutures can be connected to a single boneanchor. Double and triple loading of bone anchors, however, increasesthe forces applied to the bone anchor and increases the likelihood thatthe bone anchor will fail by being pulled out of the bone into which itis secured.

Bone anchors can fail for various reasons. One reason is that existingbone anchors are not threaded to the proximal end of the anchor wherethe anchor meets the surface of the bone in the hard cortical boneregion. In existing bone screws, the proximal end is not threadedbecause the driver tool used to insert the bone anchor fits over a hexshaped protrusion. The hex protrusion cannot extend above the bonesurface so the screw is driven into the bone until the protrusion isbelow the surface. Since the protrusion has no threads, the bone anchordoes not engage the bone near the surface, but only the soft cancellousbone beneath the cortical bone layer. This feature of existing boneanchors is very problematic because it prevents a practitioner fromplacing the threads of the bone anchor in the harder cortical bone,which is near the bone surface.

Some existing anchors engage the sutures above the anchor threads. Suchscrews have an eyelet formed in the protrusion used to drive the screw.Sutures are looped in the eyelet and fed through the driver tool.Because the attachment point for the sutures is above the threads, thethreaded portion of the bone anchor experiences a high torque momentwhen a force is applied by the suture to the attachment point.Consequently, existing bone anchors are prone to experience a certaindegree of movement within the soft bone layer. In some cases, the boneanchor can retreat from the bone and rub against soft tissues overlayingthe bone anchor. This may result in the irritation or damage of suchtissues.

Recently, bone screws have been used that place the attachment point forthe sutures within the body of the screw, specifically within the boreof the screw. In these screws an attachment site within the bore iscreated using a small piece of suture. The ends of the suture are fedthrough holes near the proximal end of the screw to form a small sutureloop within the bore. Knots are tied in the end of the suture to preventthe ends from passing back though the holes. The suture loop within thebore provides an anchoring point for threading sutures used to securetissue in a surgical procedure.

One problem with these screws is that the knots that hold the sutureloop can come untied and/or break, which releases the sutures anchoredto the suture loop. This problem is particularly difficult to fix oncethe screw has been placed in a patient because it would require thesurgeon to remove the screw from the patient. An additional problem withusing suture loops as an attachment mechanism is that the suturematerial can fray as the anchored sutures slide on it. Furthermore, whenloading multiple sutures on the suture loop, the suture loop can flexand cause the sutures to bunch together. When a practitioner is using asuture the practitioner needs the suture to freely slide in the boneanchor. The friction and/or pinching that a suture loop can causebetween lengths of suture can cause suture capture, which isundesirable.

Therefore, what is needed is a bone anchor that better engages itssurrounding bone tissue and allows greater forces to be applied to thebone anchor without becoming dislodged or failing. In addition, a boneanchor is needed that can reduce suture capture.

BRIEF SUMMARY OF THE INVENTION

The bone anchors of the present invention overcome the disadvantages ofthe prior art discussed above by providing improved suture attachmentsites and improved threads for engaging bone tissue. In an exemplaryembodiment, the bone anchor of the present invention has an anchor bodyextending between a proximal end and a distal end. A continuous threadextends around the anchor body and is configured to engage both corticaland cancellous bone tissue. The anchor body includes an interior surfacethat defines a bore that opens at the proximal end of the anchor body.One or more transverse pins are placed in and across the bore interiorto provide one or more locations within the interior of the anchor bodyfor looping one or more sutures.

According to one embodiment, the pins are placed deep within the bore ofthe anchor body. This feature allows room for a socket to be formed inthe proximal end of the anchor body where a driver tool can be insertedfor driving the bone anchor into a bone. Because the driver tool isplaced on the interior of the bone anchor, the anchor body can bethreaded to the proximal end. Threading the proximal end of the anchorbody provides the bone anchor with the ability to better engage thecortical bone near the surface of the bone.

The placement of the pins also provides a more central location foranchoring sutures. The more centrally anchored sutures exert a force onthe anchor body that is more evenly distributed and more aligned withthe axis of the bone anchor. Consequently, the bone anchor can betterdistribute the exerted force to the surrounding bone tissue withoutcausing the bone tissue to weaken so as to cause loosening or withdrawalof the bone anchor.

The pins disposed within the bore of the anchor body also provide abetter attachment mechanism for attaching a suture than exists in theprior art. The pins are securely fixed to the anchor body. Unlike thebone anchors in the prior art, the bone anchors of the present inventiondo not rely on knots to secure sutures within the bore. In addition, thepins are made of a material that does not fray and is less likely tobreak.

Double and triple loading of the bone anchor with more than one sutureis more easily accomplished with a pin because the pins provideindividual attachment locations for each additional suture. In oneexemplary embodiment, two pins are disposed in the bore at right anglesto each other. Two sutures are loaded on the lower pin with the upperpin separating the two sutures. In another embodiment, the upper pin isalso loaded with a suture. This latter configuration properly spacesthree sutures and minimizes friction and suture capture among the threesutures.

In an exemplary embodiment, the anchor body has a non-threaded portionat the distal end that forms a stabilizing extension. The extensionprovides additional stability to the bone anchor by reducing thetendency of the anchor body to move or rotate laterally. Bone anchorsare often placed in a bone at an angle. Much like a longer tent stake isless likely to give out, the extension of the bone anchor of the presentinvention helps prevent the bone anchor from becoming dislodged.Stabilizing the bone anchor reduces the likelihood that the bone anchorwill fail and allows the bone anchor to be safely loaded with moresutures.

In yet another embodiment, the anchor body is a screw that includes aportion of fine threads and a portion of coarse threads. The finethreads are configured to engage hard bone tissue, such as corticalbone, and the coarse threads are configured to engage soft bone tissue,such as cancellous bone. A portion of the threads are made finer byincreasing the root diameter and increasing the surface angle of thethread. The pitch of the coarse threads and fine threads is kept thesame such that the proximal threads can follow the impression created bythe distal threads as the bone anchor is driven into a bone.

Optimizing the thread pattern for engaging different types of bonetissue allows the bone anchor to better engage adjacent bone tissue.Because the bone anchor can better engage adjacent bone tissue, the boneanchor can be loaded with additional sutures without compromisingstability of the bone anchor. The additional sutures per anchor reducethe stress placed on each individual suture through the soft tissue,which helps prevent the sutures from cutting through the soft tissue.

These and other objects and features of the present invention willbecome more fully apparent from the following description and appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

To further clarify the above and other advantages and features of thepresent invention, a more particular description of the invention willbe rendered by reference to specific embodiments thereof which areillustrated in the appended drawings. It is appreciated that thesedrawings depict only typical embodiments of the invention and aretherefore not to be considered limiting of its scope. The invention willbe described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 is a perspective view of an exemplary bone anchor according tothe invention;

FIG. 2 is a cross-sectional view of the bone anchor of FIG. 1 showing abore extending through the anchor body;

FIG. 3 is a proximal end view of the bone anchor of FIG. 1 showing adrive socket and two perpendicularly-arranged pins within the bore;

FIG. 4 is a cross-sectional view of the bone anchor of FIG. 1 with threesutures being looped around the two pins disposed in the bore;

FIG. 5A illustrates an alternative embodiment of an exemplary boneanchor of the invention having finer proximal threads for engaging hardcortical bone and coarser distal threads for engaging soft cancellousbone;

FIG. 5B illustrates the bone anchor of FIG. 5A with double flute threadon the cortical portion of the bone anchor;

FIG. 6 illustrates the bone anchor of FIG. 5A placed within a bone suchthat the fine threads engage a hard cortical bone region and coarsethreads engage a soft cancellous bone region; and

FIG. 7 illustrates an exemplary bone anchor of the invention placed in ahumerus bone of a person with sutures attached to the bone anchoringbeing looped through and securing the person's rotator cuff.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

With reference to FIG. 1, exemplary embodiments of the present inventionare directed to an improved bone anchor 10 for affixing soft tissue tobone, such as in a rotator cuff repair surgery. Bone anchor 10 has ananchor body 12, which extends between a proximal end 14 and a distal end16. Distal end 16 of anchor body 12 has a non-threaded portion thatforms a stabilizing extension 18. Stabilizing extension 18 helps preventlateral movement of anchor body 12 within bone tissue during use. Anchorbody 12 further comprises a threaded portion, which includes threads 20for engaging bone tissue.

Proximal end 14 includes an opening 30, which provides access to ahollow interior bore 30 of anchor body 12. A hex socket 22 is formed inbore 30 of anchor body 12, which allows bone anchor 10 to be driven intoa bone using a hex driver. It will be appreciated that bore 30 of anchorbody 12 can have any other desired shape, such as triangular, square,pentagonal, star-shaped, oval, etc. Transverse pins 23 a and 23 b aredisposed through anchor body 12 and provide attachment points forlooping sutures thereon.

FIG. 2 illustrates a cross-sectional view of bone anchor 10. In anexemplary embodiment, anchor body 12 has a length of about 8 to about 15mm, a major diameter 26 of about 5 mm, and a root diameter 24 of about3.5 mm. Anchor body 12 can have sizes other than these; however, thesize of anchor body 12 is limited by the size of the bone where the boneanchor 10 is to be placed. For example, in rotator cuff repair surgery,increasing the diameter of anchor body 12 can reduce the number of boneanchors 10 that can be positioned at the repair site.

Bone anchor 10 has threads 20 that wrap continuously around anchor body12 in a desired (e.g., clockwise) direction. The pattern of threads 20determines in part how bone anchor 10 engages surrounding bone tissue.In one embodiment, threads 20 make about six turns around anchor body 12and extend toward proximal end 16.

As shown in FIG. 2, major diameter 26 and root diameter 24 may taperslightly inward toward distal end 16. The slight taper causes thethreads 20 to engage bone tissue more tightly as the bone anchor 10 isdriven further into a bone. Of course, bone anchor 10 can have threadsthat taper more or less depending on a practitioner's preference and/orthe needs of a patient.

Anchor body 12 also has a non-threaded portion at distal end 16, whichforms stabilizing extension 18. Stabilizing extension 18 is generallycylindrical and typically has a width less than root diameter 24. In oneembodiment, the length of extension 18 is more than about 20% of thelength of the threaded portion of anchor body 10. In another embodiment,extension 18 is more than 100% the length of the threaded portion and inyet another embodiment, more than about 200% of the length of thethreaded portion.

In one embodiment, extension 18 is configured to be inserted into apilot hole drilled into the bone where bone anchor 10 is to be placed.Preparing a pilot hole reduces the risk that insertion of the screw in abone will cause damage to bone anchor 10 and/or fracture bone tissue asthe bone anchor 10 is inserted into the bone. Preventing damage to boneanchor 10 and surrounding bone tissue reduces the chances that boneanchor 10 will become loosened or fail during use. In anotherembodiment, the bone anchor can have a self drilling distal end.

Anchor body 12 is advantageously made from a strong biocompatiblematerial, such as a titanium alloy or stainless steel. Alternatively,anchor body 12 can be made from a biodegradable material, such aspoly-l-lactic acid (PLLA) that can be absorbed into adjacent bone tissueover time as the repair site heals. Other biocompatible and/orbiodegradable materials suitable for use in bone anchors are known tothose skilled in the art.

Bore 30 opens at proximal end 14 to provide access to the interior ofanchor body 12. In an exemplary embodiment, a proximal portion of bore30 is hexagonally shaped to form a hex socket 22 for receiving a hexdriver. This female type driver tool engagement mechanism eliminates theneed to have a protruding proximal end 16. Instead, proximal end 16 issubstantially flat and can be placed at or just below a bone surface, asdiscussed more fully below.

As shown in FIGS. 2 and 3, hex socket 22 can be wider than the distalportion of bore 30. For example, a ridge 34 can be formed at the distalend of hex socket 22. Ridge 34 acts as a stop to limit how deep a hexdriver can be inserted therein (e.g., to protect post 23 b and/or asuture attached thereto). Alternatively, the insertion depth of a hexdriver can be controlled by placing a ridge of material on the hexdriver. In this case, insertion of the driver would be stopped when theridge on the driver engages the proximal end 16 of the anchor body 12.

The distal portion of bore 30 also contains one or more transverse pinsfor looping sutures thereon. Pins 23 a and 23 b are formed or insertedin anchor body 12 lying across bore 30. The diameter of pins 23 a and 23b are selected such that there is sufficient space between pin 23 a andpin 23 b and interior surface 28 for passing a suture around the pins 23a and 23 b. In addition to providing a location for looping sutures,pins 23 a and 23 b provide additional structural support (i.e., anendoskeleton) to anchor body 12.

Pins 23 a and 23 b are disposed in bore 30 substantially non-parallel toeach other. As illustrated in FIG. 3, in one embodiment, pins 23 a and23 b are at right angles to each other. Offsetting pins 23 a and 23 bexposes portions of pin 23 a that would otherwise be occluded from thetop by pin 23 b. Such a configuration allows a suture to be loaded onpin 23 a on either side of pin 23 b, as shown in FIG. 4.

Bone anchor 10, in FIG. 4, is illustrated loaded with three sutures 36a, 36 b, and 36 c (collectively sutures 36). Pin 23 a is shown loadedwith sutures 36 a and 36 b extending on either side of pin 23 b. Pin 23b has a single suture 36 c loaded thereon. Each suture has its own spaceto slide on its respective pin 23 a or 23 b. The proper spacing ofsutures 36 in bone anchor 10 prevents sutures 36 from rubbingextensively or getting caught on one another.

Another advantageous feature of pins 23 a and 23 b is their positiondistal to hex socket 22 and within bore 30. Pins 23 a and 23 b areplaced within bore 30 such that the forces applied by sutures 36 aretransferred to a more central location within anchor body 12. Forcesapplied to bone anchor 10 below the surface of a bone are less likely tocause bone anchor 10 to become loosened or dislodged. Pins 23 a and 23 bare placed below hex socket 22 so a hex driver can be inserted withouthitting the pins. This placement also allows sutures to be threadedthrough a hole in a driver tool (not shown) so that bone anchor 10 canbe installed pre-loaded with sutures.

While bone anchor 10 has been illustrated with two pins (i.e., pins 23 aand 23 b), bone anchor 10 may have more or fewer pins depending on therequired number of sutures and/or the space available within bore 30 forplacing more sutures. For instance, in another embodiment, the anchorbody 12 may have a single post with one or more sutures loaded thereon.Furthermore, a second pin can be disposed in bore 30 even where suturesare to be placed only on one pin, with the second pin being used solelyto separate sutures. In addition, a second pin can be placed in anchorbody 12 for structural support only.

Pins 23 a and 23 b are made from a strong metal or synthetic fiber so asto provide a rigid attachment point for sutures 36. In an exemplaryembodiment, pins 23 a and 23 b are cylindrical to provide a smoothsurface for sutures 36 to slide against. While pins 23 a and 23 b areillustrated as straight, pins 23 a and 23 b can be bent or have shapesother than cylindrical. Straight pins, however, can be more easilyplaced in anchor body 12 and therefore can reduce the cost andcomplexity of manufacturing bone anchor 10. The foregoing and similarattachment devices are examples of rigid attachment means for attachinga suture to an anchor.

In one embodiment, one or both of pins 23 a and 23 b are made from aradioopaque material such as titanium or stainless steel. A radioopaquepin can be used with a radiotransparent anchor body, such as an anchorbody made from a biodegradable material such as PLLA. This configurationof materials allows a practitioner to identify and locate bone anchor 10in a radiograph when bone anchor 10 is made mostly of biodegradablematerials.

The bone anchor according to the present invention need not be formed asa threaded device, but can also be formed as a tap-in type anchor. Also,the measurements, angles and ratios between the dimensions of the boneanchor can be varied from those described above and in the followingalternative embodiment so as to be suitable for the conditions andapplications in which the bone anchor is to be used.

FIG. 5A shows an alternative embodiment of the bone anchor of thepresent invention having a section of finer threads 38 at the proximalend 16 and a section of coarser threads 40 distal thereto. Fine threads38 and coarse threads 40 have the same major diameter 42 which has aslight taper illustrated by lines 44 a and 44 b. Fine thread 38 andcoarse threads 40, have different root diameters 46 and 48 respectively.Root diameters 46 and 48 have a slight taper similar to major diameterthe taper shown by lines 44 a and 44 b.

Fine threads 38 are finer because they have a wider root diameter 46.Root diameter 46 of fine thread 38 is wider than root diameter 48 ofcoarse threads even after subtracting out the increase in width due tothe overall taper of anchor body 12 as illustrated by lines 44 a and 44b. Fine threads 38 have root diameter 46 and a major diameter 42 thatare configured to engage harder bone. Coarse threads 40 have a rootdiameter 48 and major diameter 42 that are configured to engage softbone. In an exemplary embodiment, major diameter 42 is about 5.3 mm,root diameter 46 is about 4.8 mm and root diameter 48 is about 3.3 mm.Fine threads 38 can have a similar shape as coarse threads 40 or adifferent shape as desired. For example, fine threads 38 can have alarger or smaller thread angle.

In one embodiment, fine threads 38 have the same pitch as coarse threads40. By keeping the pitch the same between thread sections, the finerthreads 38 will be able to use the same impression cut by coarse threads40.

FIG. 5B shows yet another alternative embodiment of the presentinvention where fine threads 38 form a double flute. A first flute 39 afollows the thread pattern of coarse threads 40 such that first flute 39a follows the grooves created by coarse threads 40 as the bone anchor 10is driven into a bone. In an exemplary embodiment, second flute 39 b hasthe same pitch as first flute 39 a. Second flute 39 b can have a similarshape as flute 39 a or a different shape as desired. For example,threads 39 b can have a larger or smaller thread angle and/or majordiameter.

FIG. 6 shows bone anchor 10 disposed in a typical bone 50 having acortical bone region 52 and a cancellous bone region 54. Cortical boneregion 52 comprises dense bone, while cancellous bone region 54comprises bone that is soft or spongy. When bone anchor 10 is properlyinserted into bone 50, fine threads 38 engage the hard cortical boneregion 52 and coarse threads 40 engage the softer cancellous bone region54.

In manufacturing bone anchor 10, in accordance with the presentinvention, anchor body 12 and posts 23 can be cast and formed in a die.Alternatively anchor body 12 can be cast or formed and posts 23 a and 23b inserted later. For instance, anchor body 12 can be cast and formedfrom PLLA. Anchor body 12 can then be drilled to prepare holes forstainless steel pins 23 a and 23 b.

The suture anchors according to the present invent can be distributed topractitioners with one or more of sutures 36 threaded through bore 30and looped to pins 23 a and/or 23 b. In one method of manufacturing boneanchor 10, sutures 36 are looped on pins 23 a and 23 b as pins 23 a and23 b are inserted into anchor body 12.

An example of a type of suture suitable for use in conjunction with thebone anchor of the present invention is #2 braided polyester. If morethan one strand of sutures 36 is used, the sutures can be a differentcolor such that a practitioner can more easily pair the ends of thesutures during a surgical operation.

FIG. 7 illustrates the use of bone anchor 10 in a rotator cuff repairsurgery. Bone anchor 10 is placed in humerus bone 54, and sutures 36 arepassed through rotator cuff 56 and tied. Before bone anchor 10 isinserted in humerus bone 54 a pilot hole may be drilled. Bone anchor 10is inserted into the pilot hole using a driver tool until proximal end14 is substantially flush with the outer surface of humerus bone 54.Bone anchor 10 is advantageously placed in humerus bone 54 at an angleto the tangent of the humerus bone, also known as the “dead man'sangle.”

Because bone anchor 10 is placed in humerus bone 54 at an angle,extension 18 provides a mechanical advantage against bone anchor 10moving laterally and opening the angle to the tangent. By preventinglateral movement, extension 18 prevents sutures 36 from loosening oncesutures 36 have been properly tied. In addition, if bone anchor 10 wereto move within bone 54, bone anchor 10 can become dislodged and fail.Extension 18 does not have threads thereon, which reduce friction asbone anchor 10 is driven into a pilot hole.

Proximal end 14 of bone anchor 10 is substantially flat ornon-protruding such that bone anchor 10 can be placed at or just belowthe surface of bone 54. Threads extend to proximal end 14 such that boneanchor 10 has maximum engagement with bone 54. The opening at proximalend 14 also allows for sutures 36 to exit the bore. The opening of thebore is smooth such that sutures 36 can easily slide thereon.

Sutures 36 exit bone anchor 10 at proximal end 14 and are drawn throughthe soft tissue of rotator cuff 56. Sutures 36 can be spaced to moreevenly distribute the load exerted by rotator cuff 56. As shown in FIGS.5 and 7, sutures 36 exert a force on bone anchor 10 on the pins in thebone and at proximal end 14. Because proximal end 14 is at or below thesurface of bone 54, less torsion is applied to bone anchor 10. Instead,the force of rotator cuff 56 is distributed vertically along the anchorbody through the pins. Consequently, bone anchor 10 is less likely to bedislodged and fail.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

What is claimed is:
 1. A suture anchor assembly for attachment of tissueto bone, the suture anchor assembly comprising: an anchor body having alongitudinal axis, a distal end forming a fixed distal tip, a proximalend forming a proximal face transverse to the longitudinal axis, aninterior bore opening at the proximal face, and threads beginning at aperiphery of the proximal face and extending toward the distal end; asocket formed in a proximal portion of the interior bore, opening at theproximal face, and being configured to receive a correspondingly shapeddriver; a rigid member fixedly and non-removably attached to the anchorbody and in communication with the interior bore, wherein the rigidmember is positioned transverse to the longitudinal axis of the anchorbody at a location distal to the socket and fixed relative to theproximal face, the socket, and the distal tip; and a tissue securingsuture looped around the rigid member and having free ends forattachment to soft tissue, wherein the tissue securing suture extendsoutside the anchor body and exits through the socket at the proximalface of the anchor body.
 2. The suture anchor assembly according toclaim 1, wherein the anchor body comprises stainless steel.
 3. Thesuture anchor assembly according to claim 1, wherein the rigid member isa pin that comprises stainless steel.
 4. The suture anchor assemblyaccording to claim 1, wherein the anchor body is tapered.
 5. The sutureanchor assembly according to claim 1, wherein the distal end of theanchor body is self drilling.
 6. The suture anchor assembly according toclaim 1, wherein the threads extend partially to the distal end of theanchor body.
 7. The suture anchor assembly according to claim 1, whereinthe rigid member is disposed in a distal portion of the interior bore.8. The suture anchor assembly according to claim 7, wherein the socketis hexagonally shaped and the distal portion of the interior bore iscylindrical, wherein the tissue securing suture is looped around therigid member in the distal portion of the interior bore.
 9. The sutureanchor assembly according to claim 1, wherein the socket includes aplurality of surfaces configured to contact a correspondingly shapeddriver, the plurality of surfaces including first and second planarfaces that intersect along the longitudinal axis of the anchor body. 10.The suture anchor assembly according to claim 1, wherein the socketincludes first and second planar faces configured to contact acorrespondingly shaped driver, and wherein the rigid member is disposedin the distal portion of the interior bore.
 11. The suture anchorassembly according to claim 1, wherein the socket is hexagonal and adistal portion of the interior bore is cylindrical, wherein the rigidmember comprises a pin that is transverse to the longitudinal axis andpositioned in the distal portion of the interior bore.
 12. The sutureanchor assembly according to claim 1, wherein the socket includes planarsurfaces which are parallel to the longitudinal axis of the anchor body.13. The suture anchor assembly according to claim 1, further comprisinga ridge formed at a distal end of the socket that acts as a stop tolimit how deep a driver can be inserted into the interior bore.
 14. Thesuture anchor assembly according to claim 1, wherein the rigid member ispositioned across a distal portion of the interior bore.
 15. The sutureanchor assembly according to claim 14, wherein the rigid member has anaxis that is generally perpendicular to the longitudinal axis of theanchor body.
 16. The suture anchor assembly according to claim 1,wherein the free ends of the tissue securing suture are unattached toeach other.
 17. The suture anchor assembly according to claim 1, whereinthe free ends of the tissue securing suture are free to move relative toeach other.
 18. The suture anchor assembly according to claim 1, whereinthe free ends of the tissue securing suture include a first loose endand a second loose end.
 19. The suture anchor assembly according toclaim 1, wherein the tissue securing suture is slidably looped aroundthe rigid member.
 20. The suture anchor assembly according to claim 1,wherein the rigid member is straight.
 21. The suture anchor assemblyaccording to claim 1, wherein the socket has a shape selected from thegroup consisting of triangular, square, pentagonal, star-shaped, andoval.
 22. The suture anchor assembly according to claim 1, wherein adistal portion of the interior bore has a size that prevents a driverfrom entering therein, and wherein the rigid member is located in thedistal portion of the interior bore.
 23. The suture anchor assemblyaccording to claim 22, wherein the distal portion of the interior boreis cylindrical and has a smaller diameter than the socket.
 24. Thestructure anchor assembly according to claim 1, further comprising adriver having an end corresponding to a shape of the socket.
 25. Thesuture anchor assembly according to claim 24, wherein the shape of thesocket is selected from the group consisting of hexagonal, triangular,square, pentagonal, star-shaped, and oval.
 26. The suture anchorassembly according to claim 24, wherein a distal portion of the interiorbore has a size that prevents the end of the driver from enteringtherein.
 27. The suture anchor assembly according to claim 26, whereinthe distal portion of the interior bore is cylindrical and has a smallerdiameter than the socket.
 28. A suture anchor assembly for attachment oftissue to bone, the suture anchor assembly comprising: an anchor bodyhaving a longitudinal axis, a distal end forming a fixed distal tip, aproximal end forming a proximal face transverse to the longitudinalaxis, threads extending fully to a periphery of the proximal face, andan interior bore opening at the proximal face, a proximal portion of theinterior bore forming a socket configured to receive a driver and beingwider than a distal portion of the interior bore in order to preventinsertion of the driver into the distal portion; a rigid member fixedlyand non-removably attached to the anchor body in communication with andpositioned distal to the socket of the interior bore, wherein the rigidmember provides a location that is fixed relative to the proximal face,the socket, and the distal tip for looped attachment of a tissuesecuring suture; and a driver having a size and shape so as to bepositionable within the socket formed in the proximal portion of theinterior bore without hitting the rigid member, the driver furtherincluding a hole through which the tissue securing suture, when attachedto the anchor body, can be threaded.
 29. The suture anchor assemblyaccording to claim 28, wherein the anchor body comprises stainlesssteel.
 30. The suture anchor assembly according to claim 28, wherein therigid member comprises stainless steel.
 31. The suture anchor assemblyaccording to claim 28, wherein the anchor body is tapered.
 32. Thesuture anchor assembly according to claim 28, wherein the distal end ofthe anchor body is self drilling.
 33. The suture anchor assemblyaccording to claim 28, wherein the threads extend partially to thedistal end of the anchor body.
 34. The suture anchor assembly accordingto claim 28, wherein the rigid member is disposed in the distal portionof the interior bore.
 35. The suture anchor assembly according to claim28, wherein the socket is hexagonally shaped and the distal portion ofthe interior bore is cylindrical, wherein the driver includes ahexagonally shaped end configured to engage the hexagonally shapedsocket.
 36. The suture anchor assembly according to claim 28, whereinthe socket includes a plurality of surfaces configured to engage acorrespondingly sized and shaped end of the driver, the plurality ofsurfaces including first and second planar faces that intersect alongthe longitudinal axis of the anchor body.
 37. The suture anchor assemblyaccording to claim 36, wherein the rigid member is disposed in thedistal portion of the interior bore.
 38. The suture anchor assemblyaccording to claim 37, wherein the socket is hexagonal and the distalportion of the interior bore is cylindrical, wherein the driver includesa hexagonal end configured to engage the socket.
 39. The suture anchorassembly according to claim 36, wherein the socket includes planarsurfaces which are parallel to the longitudinal axis of the anchor body.40. The suture anchor assembly according to claim 28, wherein the distalportion of the interior bore is cylindrical.
 41. The suture anchorassembly according to in claim 28, wherein the rigid member istransverse to the anchor body.
 42. The suture anchor assembly accordingto claim 41, wherein an axis of the rigid member is generallyperpendicular to the longitudinal axis of the anchor body.
 43. Thesuture anchor assembly according to claim 28, wherein the rigid memberis straight.
 44. A suture anchor for use in attaching tissue to bone,comprising: an anchor body having a longitudinal axis, a distal endforming a fixed distal tip, a proximal end forming a proximal facetransverse to the longitudinal axis, an interior bore opening at theproximal face, threads beginning at a periphery of the proximal face andextending toward the distal end, and a socket formed in the interiorbore, opening at the proximal face, and being configured to receive acorrespondingly shaped driver; and a transverse pin fixedly andnon-removably attached to the anchor body and disposed distal to thesocket within the interior bore, wherein the transverse pin ispositioned transverse to the longitudinal axis of the anchor body andprovides a location that is fixed relative to the proximal face, thesocket, and the distal tip for looped attachment of at least one tissuesecuring suture.
 45. The suture anchor according to claim 44, whereinthe anchor body comprises stainless steel or titanium.
 46. The sutureanchor according to claim 44, wherein the transverse pin comprisesstainless steel or titanium.
 47. The suture anchor according to claim44, wherein the anchor body is tapered.
 48. The suture anchor accordingto claim 44, wherein the distal end of the anchor body is self drilling.49. The suture anchor according to claim 44, wherein the threads extendpartially to the distal end of the anchor body.
 50. The suture anchoraccording to claim 44, wherein the socket includes a plurality ofsurfaces configured to engage a correspondingly shaped driver, theplurality of surfaces including first and second planar faces.
 51. Thesuture anchor according to claim 44, wherein the transverse pin has anaxis that is transverse to the longitudinal axis of the anchor body. 52.The suture anchor according to claim 51, wherein the axis of thetransverse pin is generally perpendicular to the longitudinal axis ofthe anchor body.
 53. The suture anchor according to claim 44, whereinthe transverse pin is straight.
 54. The suture anchor according to claim44, wherein the socket has a shape selected from the group consisting ofhexagonal, triangular, square, pentagonal, star-shaped, and oval. 55.The suture anchor according to claim 54, wherein a portion of theinterior bore distal to the socket is cylindrical and has a smallerdiameter than the socket.
 56. The suture anchor according to claim 44,wherein the transverse pin extends through opposing sides of the anchorbody so as to be visible on opposing surfaces of the anchor body.
 57. Asuture anchor assembly for attachment of tissue to bone, the sutureanchor assembly comprising: an anchor body having a longitudinal axis, adistal end forming a fixed distal tip, a proximal end forming a proximalface transverse to the longitudinal axis, an interior bore opening atthe proximal face, threads beginning at a periphery of the proximal faceand extending toward the distal end, and a socket formed in the interiorbore, opening at the proximal face, and being configured to receive acorrespondingly shaped driver; a rigid member fixedly and non-removablyattached to the anchor body, wherein the rigid member is comprised of arigid material and is positioned transverse to the longitudinal axis ofthe anchor body at a location distal to the socket and fixed relative tothe proximal face, the socket, and the distal tip; and a flexible suturelooped around the rigid member.
 58. The suture anchor assembly accordingto claim 57, wherein the socket is hexagonally shaped and a distalportion of the interior bore is cylindrical.
 59. The suture anchorassembly according to claim 57, wherein the rigid member has an axisthat is generally perpendicular to the longitudinal axis of the anchorbody.
 60. The suture anchor assembly according to claim 57, wherein therigid member comprises a transverse pin.
 61. The suture anchor assemblyaccording to claim 57, wherein the flexible suture includes free endswhich are unattached to each other.
 62. The suture anchor assemblyaccording to claim 57, wherein the flexible suture extends beyond andexits the socket at the proximal face of the anchor body.
 63. The sutureanchor assembly according to claim 57, further comprising a driverhaving a size and shape so as to be positionable within the socket. 64.A suture anchor assembly for attachment of tissue to bone, the sutureanchor assembly comprising: an anchor body having a longitudinal axis, adistal end forming a fixed distal tip, a proximal end forming a proximalface transverse to the longitudinal axis, threads extending fully to aperiphery of the proximal face, and an interior bore opening at theproximal face, a proximal portion of the interior bore forming a socketconfigured to receive a driver and being wider than a distal portion ofthe interior bore in order to prevent insertion of the driver into thedistal portion; a rigid member fixedly and non-removably attached to theanchor body, wherein the rigid member is comprised of a rigid materialand is positioned transverse to the longitudinal axis of the anchor bodyat a location distal to the socket and fixed relative to the proximalface, the socket, and the distal tip, wherein the rigid member providesa location distal to the socket for looped attachment of a flexiblesuture; and a driver having a size and shape so as to be positionablewithin the socket formed in the proximal portion of the interior borewithout hitting the rigid member, the driver further including a holethrough which the flexible suture, when attached to the anchor body, canbe threaded.
 65. The suture anchor assembly according to claim 64,wherein the threads define a proximal threaded anchor body region and adistal threaded anchor body region, and wherein the rigid member ispositioned in the distal threaded anchor body region.
 66. The sutureanchor assembly according to claim 64, further comprising a flexiblesuture looped around the rigid member.
 67. The suture anchor assemblyaccording to claim 66, wherein the flexible suture includes free endswhich are unattached to each other.
 68. The suture anchor assemblyaccording to claim 66, wherein the flexible suture extends beyond andexits the socket at the proximal face of the anchor body.
 69. The sutureanchor assembly according to claim 66, further comprising a secondsuture attachment member, wherein the second suture attachment member ispositioned within the interior bore at a location proximal to the rigidmember and distal to the proximal face.
 70. The suture anchor assemblyaccording to claim 69, wherein the second suture attachment membercomprises a transverse pin extending across the interior bore.
 71. Thesuture anchor assembly according to claim 69, further comprising asecond flexible suture looped around the second suture attachmentmember.
 72. The suture anchor assembly according to claim 71, whereinthe second flexible suture is threaded through the hole of the driver.73. A suture anchor for use in attaching tissue to bone, comprising: ananchor body having a longitudinal axis, a distal end forming a fixeddistal tip, a proximal end forming a proximal face transverse to thelongitudinal axis, an interior bore opening at the proximal face,threads beginning at a periphery of the proximal face and extendingtoward the distal end, and a socket formed in the interior bore andopening at the proximal face configured to receive a correspondinglyshaped driver; and a rigid member fixedly and non-removably attached tothe anchor body, wherein the rigid member is comprised of a rigidmaterial and is positioned transverse to the longitudinal axis of theanchor body at a location distal to the socket and fixed relative to theproximal face, the socket, and the distal tip, wherein the rigid memberprovides a location distal to the socket for looped attachment of aflexible suture.
 74. The suture anchor according to claim 73, whereinthe threads define a proximal threaded anchor body region and a distalthreaded anchor body region, and wherein the rigid member is positionedin the distal threaded anchor body region.
 75. The suture anchoraccording to claim 73, further comprising a flexible suture loopedaround the rigid member.
 76. The suture anchor according to claim 75,wherein the flexible suture includes free ends which are unattached toeach other.
 77. The suture anchor according to claim 75, wherein theflexible suture extends beyond and exits the socket at the proximal faceof the anchor body.
 78. The suture anchor according to claim 75, furthercomprising a second suture attachment member, wherein the second sutureattachment member is positioned within the interior bore at a locationproximal to the rigid member and distal to the proximal face.
 79. Thesuture anchor according to claim 78, wherein the second sutureattachment member comprises a transverse pin extending across theinterior bore.
 80. The suture anchor according to claim 78, furthercomprising a second flexible suture looped around the second sutureattachment member.